NYC Philatelic control unit mark. Question from a newbie.

Hello!
I would like to share these pictures of a cover in my WWII US Censorship colection (and make some silly questions!)
1944 from London, UK to Newgulf (TX), USA. Registered letter. Philatelic mail from WHITFIELD KING & Co.
Front:
-Postage stamps 3d + 2 1/2 c (I would appreciate any information about this postal rate)
-British censor red mark type"Crown" PASSED PER 34".
- BPA oval mark dated 9/3/44.
-US Customs PASSED FREE Port of New York GPO violet rectangular mark.
- US censorship "Examined by" cellophane tape with censor numbers 9827 (very blurred) & 20001 (both on Broderick & Mayo philatelic control unit series)
Back:
- A black handstamp (two lines) "RECEIVED BY P.C.U. / DATE APR 6 1944". My first question: Is this a reported censorship
mark from the PCU in New York?. If not, what is it?
- Oval cachet NEW YORK REG´Y 3/30/1944 (US arrival date)
-Customs mark from Port of New York Philatelic Unit. Second question: Is that mark related with PCU or nothing to do?
- Circular cachet (transit) Saint Louis MO. MAR/27/1944.
Thanks in advance.
Best regards.
Jose M.
I would like to share these pictures of a cover in my WWII US Censorship colection (and make some silly questions!)
1944 from London, UK to Newgulf (TX), USA. Registered letter. Philatelic mail from WHITFIELD KING & Co.
Front:
-Postage stamps 3d + 2 1/2 c (I would appreciate any information about this postal rate)
-British censor red mark type"Crown" PASSED PER 34".
- BPA oval mark dated 9/3/44.
-US Customs PASSED FREE Port of New York GPO violet rectangular mark.
- US censorship "Examined by" cellophane tape with censor numbers 9827 (very blurred) & 20001 (both on Broderick & Mayo philatelic control unit series)
Back:
- A black handstamp (two lines) "RECEIVED BY P.C.U. / DATE APR 6 1944". My first question: Is this a reported censorship
mark from the PCU in New York?. If not, what is it?

- Oval cachet NEW YORK REG´Y 3/30/1944 (US arrival date)
-Customs mark from Port of New York Philatelic Unit. Second question: Is that mark related with PCU or nothing to do?
- Circular cachet (transit) Saint Louis MO. MAR/27/1944.
Thanks in advance.
Best regards.
Jose M.