DLA-questions

Hello dear members.
I received the DLA renewal form on the 10h of April. it’s been 3 years since my last claim and due to all “renovations” to form and claiming process, I am not sure I know what to do(apart from completing the form) . Can someone let me know what have changed, how hard it is nowadays to complete the form and to get the benefit rates that one deserves?
The form, I think, came too early this time, or maybe I’m wrong, my benefit due in august? Also is there a time limit for a submitting the form? I think, I’ve read somewhere that the time limit is two weeks, is it right? My form and the letter accompanying it, doesn’t say to return the form by any date, also it says that they will not contact me again. When do you think is the best to return the form? Although, I have been through all this 3 years ago, I fill myself like a total newbee, and have no idea where to start or what to do, sorry- do I better to seek help in completing the form? Sorry if all this was asked before, but I couldn’t find the answers on the forum. Will really appreciate your advice.