You have to activate by the 11 April. if you wait until the 11th of April then it will be valid for travel every day until 10 June.
When you use it within that period is entirely up to you. You can travel every day or one day or any other combination you please, the only restriction is you can only travel in your home country on 2 days out of the overall validity period, these 2 days can be any you choose.
Loads of people have that sales-pass/same point. In MY idea however the very last day to be able to start using/activate it is not 11 /4 but 10/4.
There are also some reports that it will automatically be assumed that day 1-when activated will be seen as used PASSday. Normally that is of course quite logic-why else would someone activate it? There may be some trick to have that rearranged so that you do not loose a passday becse of that. Same may hold for someone who turns 28 in that period and thus has to start activate it before that birthday.
AND you did not clearly state what type of pass you have bought-not all passes are valid 2 month-the cheaper ones with less days just 1 month-in such a case and in my reasoning then 9/5 would be the very last possible final day to use it.
Loads of people have that sales-pass/same point. In MY idea however the very last day to be able to start using/activate it is not 11 /4 but 10/4.
Please don’t keep repeating your own incorrect and unverified ideas. You've been told many times now that the latest possible start date is exactly 11 months after purchase. You can see that easily if you start the activation process and check what the latest selectable start date is.
There are also some reports that it will automatically be assumed that day 1-when activated will be seen as used PASSday.
That was the case for flexipasses (and you could cancel that 1st travel day), but not anymore.