Reference letters for UK citizenship

Hi all!
I am considering applying for the UK citizenship. I read here and on gov.uk about referees for UK citizenship but still don't understand a few things. Could you please help.
As many people applying for UK citizenship I am a bit confused about a referee "who has a professional standing" (Referee declaration MN1 I am referring to).

My questions:
1) Do I understand correctly that the referee should have the profession from the list of acceptable professions but still can be my friend or a neighbour? I don't have to be in the professional relationship with them right?
I mean it doesn't have to be specifically my dentist or a nurse at my local GP practise?

2) What exactly does 'chemist' mean in the list on gov.uk?
I have an Australian friend working in the NHS hospital as a pharmacist. She often refers to herself as a chemist, because in Commonwealth English it's the same thing. Is 'chemist' in the list of acceptable professions the same as pharmacist or its a chemistry scientist?

3) Can the reference letters be dated a few months earlier than I am eligible to apply for citizenship?
I am eligible to apply in June, can I still obtain letters in Feb-March?

Thank you in advance!

1) Correct. Professional engagement is only required for children.

2) I believe pharmacist (chemist) is OK.

3) Ideally very close to application date (not more than a month old) OR after application and up to the biometrics date at the latest.

Thanks a lot for a quick response!