A member of staff has noted that when setting up blocks for the year, and exporting them now, the summer times are off by an hour as the ical times are all UTC and never change.
I recreated this issue by setting up a block on the 1st of every month for a year for 9am-10am. The ical event is specified for 9am-10am UTC for every month of the year, which will be wrong come summer time.
We're using version 4.0.1.
I've checked block settings and the params file, but did not see anything that could change the ical output. I've looked at the readmes but did not see anything explaining how the right timezone is selected. I was not involved in the installation of the system, so perhaps I've overlooked some settings, but as it stands, I believe this is a bug.