Ryan93
Please refer to post #2576.
There is also a post (which I can't find) stating that applicants have been required to sign a form stating they can attend selection days on week 3 and 4 in April (wc 20th and 27th).
Because of the above I don't believe first stage assessments will be going into April week 2. I'd be surprised if they were happy to still be assessing candidates the week before the next stage! (Could be wrong though).
Which FTO in particular are you enquiring about? Might it be worth contacting them directly if you have a problem attending.