for the old inskgiving events ink was returned as regular ink but iirc it did have an expiry though i don't recall why but it may show up with an expiry now based on whatever tapas new back-end system may be since the site overhaul
the change for it to now be bonus ink is disappointing but not that surprising. it's possible events like these may have run tapas at a deficit or something (and lets not forget that tapas does need it's profits) so their way of making up for it is having folks use bonus ink on the premium or early access series which puts money back into their pockets
again it def sucks because rather than folks being able to give to any creator of their choosing it's now a limited pool of premium + early access comics and since their the big rats that make all the rules we've no choice but to follow suit or go elsewhere
i'd say for folks who are able give to ko-fis/patreons if you can or reshare stuff on social media. as for response to tapas it's basically the same as any other time people have any gripes with a company (boycotting, rescinding financial support, voicing issues/complaints in a more public place or taking work/business elsewhere)
like call me pessimistic but at the end of the day business is gonna do what business is gonna do whether people like it or not and sometimes the peoples response does things to change those decisions and other times it's just a drop of water in a big ocean so you either go with the flow or try harder to make waves