I’m also participating today! 
I started shortly after 2 p.m. and did not have time to read in one long stretch, but I managed to spend exactly 2 hours and 22 minutes reading 19 pages of 後鳥羽伝説殺人事件 (the current MMMBC evaluation pick) 
Further plans: I will read 6 more pages of 後鳥羽伝説殺人事件 (then I’ll be caught up with this week’s reading).
After that, I will switch to 怪人二十面相 (the current IBC pick). I’m more than 130 pages behind the club schedule 
but I hope to be able to catch up quite a bit tomorrow morning.
In the unlikely event of being able to completely catch up with 怪人二十面相, I will continue reading ゼロの焦点 which is an informal book club for a discussion event organized by the Japanese Society UK.