I've never had a buffer, so I've never had this problem.
No brain = no pain.
Let my readers know there's going to be a small hiatus and we'll be back to speed in a couple of weeks. This usually happens when I'm tabling at a con and gotta put all my cash towards prepping for that. It's actually happening right now lol.
panic!
in seriousness, taking a week off every month sounds good. i take a week off posting at the end of each chapter / roughly every 3 months - and if im feeling nervous about deadlines, i extend that to 2-3 weeks. never more than 3.
though thats a cure more than a prevention - prevention is about time management!! i use this spreadsheet by jason brubaker to track my progress:
i set the deadline for each chapter at the quiet week at the end of the previous, and then... hit that deadline. i set internal deadlines; i work on twaw on the weekends, so each weekend has an assigned goal, eg: all blocking, batch #1 thumbnails, etc 2 3 4, inking, colours. though thats my timeplan now that i can bang out an entire chapter before the previous one ends.
when i was a bit slower, id thumbnail and sketch 6 pages in one weekend, then ink and colour and schedule them the next weekend, so id always be adding 6 pages to the buffer for every 4 spent. id still aim to get it all done before page 1's release, but i then had 2-3 weeks wiggle room.
Hubby and I plan breaks at particular times that are things that are easy to set up and draw. Basically the style of the filler takes maybe half a week to do. If we take time to do 2 or 3 of these then we get extra time later. So we never really take the breaks when we claim we will.
This is why you should be working on a seasonal basis.
So this way you can dedicate time to work on different steps of the comic. You can dedicate a week to writing, 2 weeks for drawing, then the rest with editing/fixes.
That's the ideal way of working for me if I didn't have school.
...
This is probably not sound advice though.
I worked out a way to quickly draw pages in batches, but when I realize my buffer is about to run out, my work looks like this.
1
"Buh-fur?" What is this word? I am not familiar with this word. 
I've never had one. I don't even write much down before I do the strip every week, mostly because this is a hobby and I don't have a lot of time to devote to it like most other creators do what with working and parenting. So I just have strip ideas or jokes in my head that I know I want to do in the future but every strip I put out I likely only started doing two days prior to uploading it. Once I finally get around to doing the comic I've been planning for a decade I'll put in way more time and effort and will likely have things written out and a buffer formed and whatnot, but for now I don't have much of a choice but to do it the way I'm doing it. 
It's funny, since I've started my comic I've been seeing mentions of Jason Brubaker everywhere. He's an old acquaintance who once dated my sister (I think I might still have one of the old copies of Phobos somewhere). Seeing as we come from this small city out in the middle of nowhere it can be kind of surreal to think of someone who grew up out here as such a big name in so many industries.
.... er, sorry, unrelated response. I'll have to consider making a spreadsheet. It's a little more organization than I'm used to, but maybe that just means I need to start doing more...
Ran out of a buffer a long time ago. Never had one since. We just got to keep up with the weekly uploads or else there just isn’t an update.
the largest buffer i can maintain is 1 week ahead so im constantly in panic mode (i did try a 4-5 week buffer and couldnt keep up)
since I have an issue with my wrist I take a break from posting on Tapas and Webtoon. but my patreon fans, they come first because its obvious. however once I feel better I continue. thats really it. but while taking a break. I work ahead so I'm not in a rush when I begin posting.
I math it out ahead of time to adjust the releases for the buffer I do have. If I was uploading twice a week, it's now once. If it was once a week, it's now maybe 3 a month, or just a week break in between a "suitable" break. ie my novel NTN is releasing as ch53A, ch53B and ch53C: after part C is released, I might delay a release with a note in part C before it's released, that the next update will come a week later. For me this isn't a huge issue, since readers who want to hardcore binge can run over to my dA and go all the way up to my current section, but for Tapas I'm trying to keep it at a consistent release. but that "out of buffer" time is looming closer and closer each week and I'm just like: eventually, they'll have to deal with potentially weeks of no updates.... THE HORRORRRRR
I guess I work a bit more like @rainbowolfe and @beta1042 and just flat out cry and panic haahaha
I have a scheduled amount in the buffer and i make a page when i post a page so the buffer number stays the same.
I'm living the "dream" right now... my buffer expired sometime back in March-ish and I just haven't had one since 
Granted I kind of did it to myself...
I used up most of it in December when I took time off to do other stuff, but for some reason when I got back to it mid-january I decided "hey I've been drawing like 2-3 pages a week and uploading just 1... maybe I should start uploading 2-3 pages instead and my current buffer will maintain itself, right??"
Nope, absolutely not LOL so I just ate it all in a few weeks and was like "crap".
Uhhh at that point, if I were working on a longer project I probably would have tried to get to the end of the chapter or whatever and took some time off to rebuild. As-is this season is coming to an end shortly and was originally planned as a standalone one-shot anyways so... I decided to just tough it out and draw my 1 page a week every single week to upload xD
I think my biggest takeaway though is that I'm really not a fan of like... drawing the same content that you're uploading at the moment, if that makes sense? At it's biggest I think my buffer was only like a month and a half or so long. So even when I had one I was still kinda under pressure to keep moving briskly or risk running out... which happened. I think for my next season I'm going to instead draw like all of it up front- or at least most of it- before I start uploading. I want to be able to make it peacefully and not feel rushed all the time 
