Have they requested any additional info from you? Usually the not straight forward email indicates that a document was missed in the original application submission. Do you want to post a list of what you included in the application to see if it looks like something is missing?
I thought the "not straight-forward" email was a delaying tactic due to them having made no progress in 2 months, what with the massive backlog. If it was related to missing material, I would have thought they would request it.
Included in the application was:
1. UKVI application
2. Appendix 2
My stuff:
1. Letter from work proving I earn above the financial requirements (I'm well above it)
2. 12 months of payslips and 3 years of P60s (all printed off as my company does everything online)
3. 3 months of bank statements to back up the payslips
4. Property deeds of apartment
4. Mortgage Statement (original and copy)
5. Utilities bills, council tax bill. Original and copies
6. Notified passport.
Relationship details
1. Marriage certificate from California
2. Relationship documentation including mostly Facebook chat.
3. Photographs dating back to 2013.
My wife:
1. Cover letter detailing her status in the US
2. South American passport. She lives in LA. Old passport as well.
3. US driving license, social security, bank statement
4. Rental and Employment evidence
5. IELTS result
The only thing I can think of is that she was applying for residency in the US and that has been dragging on. I contemplated moving to the US, but with the new presidency, I thought her application would just be stalled forever.