It never has been £30 with Android Pay – that’s the limit for use with a card, and is also the point at which you have to put in the unlock code on the phone (it doesn’t work just with the phone unlocked, so it doesn’t matter if you leave the phone unlocked). As discussed above it’s also a hard limit some retailers have.
I’ve done a quick check, and can’t find mention of any upper limit beyond £30 – not in the info on my bank website, or even on any other bank website of those I’ve checked. No mention at all of £100 which I’m sure was originally the upper limit. The implication being that there is no upper limit!