How long will I have to wait for a telephone assessment for PiP?

I made an application for PiP on October 2021 and duly emailed to completed PiP2 form as requested. I received an email acknowledging that my claim for had been received but I’ve heard nothing since then. Is this normal? Should I telephone for an update on my claim? I appreciate that some people have been waiting a number of months for a decision for PiP reviews but I was under the impression that the DWP had 11 weeks from the start of the claim to make a decision (not sure where I got this information from) my other question is, if I’m successful in my claim will PiP be awarded from the date of the original claim or from when the decision is made? TIA