First thing is, don't leave. The viewership you have here won't always translate to viewership elsewhere. Unless a giant new website shows up with perfect UI and tools, don't hop websites except for your content being unreasonably censored(eg tumblr purge) or no one else being there.
That said, it's good to have mirrors and never rely on one place that's out of your control. There's DeviantART, Twitter, etc; but you can also get a website via ComicFury or Wordpress, and always have that one area you can link for as long as the site exists and you can pay for a domain(if you want a custom link). However, it's incredibly hard to market in these places, and it's much better to instead have them a page ahead of schedule and go "feel free to read on Tapas, but there's extra pages/content in (your website)!".