Word is that they may change the quorum rules for a special session. Regular sessions operate under the regular House rules but special sessions do not and they can adopt their own. So they may cut the quorum rule from 100 to 85.
How do they do that since the Quorum Rule is written in the Texas Constitution without a change/amendment to the Constitution?
I'm not quite sure how it works - that's just the rumor I've heard. It may in fact be impossible without a constitutional amendment, or it may not. Or it could have something to do with striking a quorum requirement for the non-vote readings of the bill.
Special sessions in Texas are subject to all sorts of strange little rules that make them an entirely different ball game than the regular legislature.