I use the Bergeon 6767-F (Fine) spring bar tool for all my watches, including those fitted with Oysterflex and other rubber straps.
I bought this tool which looks very similar https://www.etsy.com/listing/689589962/spring-bar-removal-tool-double-end-with.
The spring bars look different in that they have a sleeve which can be pushed in either direction but don't want be release.
Ah... well that's interesting. If they're some exotic design then I'd wait till someone with more knowledge pops up, like KJ2020 for instance.
What I would say is that I've also got cheap Chinese versions of the Bergeon tool, and invariably the cheapo ones have tips made of semi-hardened cheese and really don't get the correct "bite" on the springbar and are inclined to bend and deform at the first sign of resistance from the bar, which is why I recommended the gen Bergeon.
The rubber strap makes it a bit hard to get to the spring bar. Sure the Bergeon mentioned would work, but I use the tool that has a wider spring bar remover. Looks like a fork, but much wider than the one that takes our regular spring bars. Not sure how to explain it, so here is a link. You do not have to buy this specific tool, I found it randomly, but has both types of spring bar removal tools in one piece.
https://www.amazon.com/Spring-Bar-T...9Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=
Oh, you might be right - that didn't cross my mind, but having read the OP's description again, yes it could be the issue. If so, then the linked YouTube vid could be a life saver...I am not sure if you have shoulderless spring bars, but from your description I thought of those.
The spring bar doesn't seem to have the normal shoulders that i've seen before on others.
"With many great disasters, come many great wisdom." I'm pretty sure that's how the saying goes.Please OP, whatever you do, don't listen to any 'advice' Poppadoodle gives you re watch repair/modding without looking at some of his modding threads (and thus realising what a complete disaster he is).
Hope this helps.