Messed up royally yesterday - decided to wheel the bike out, and clean the paint (heard matt was a pita), found some advice online about using Windex without ammonia, so I did that and it looked very nice.
Then I turned my attention to cleaning the calipers inside, as I've not yet had them off on this bike - sadly I was on daycare duty at the same time, so didn't keep a very good watch on what I was doing..... and out popped a piston
Managed to fumble it back in, but when pushing it back in, another one popped out! So after much (internal so the little one didn't hear) swearing - I got everything back together. Cleaned up all the fluid that came out, and worked the pistons back in - but something was clearly not right, as a couple took a fair amount of force - even with the bleed nipple uncracked (the reservoir was already open).
Spent all evening then thinking about it, and Googling all sorts of stories...
Checked it over before going out for a family meal today, and no leaks found, so I took the caliper off and pads out, and was able to work all the pistons in by hand a few times, so hopefully no damage done - though I'll be certain to bleed the system.
Oh well, first time for such an eff up for me.