Would appreciate insight on my cold start issue

[RenaissanceMan]

2005 X5 3.0 w/211k miles. Started having cold start issues about a week ago. First start attempt of the day when temp was under 45 or so degrees would result in just cranking with no start. Would take between 2 and 5 start attempts for it to finally fire up. Did a bunch of thread searching here and went through the usual checks. Wasn't getting any error codes via INPA, fuel pressure looked to be normal, and it otherwise ran perfectly once started. Subsequent starts during the day had no problems. EDIT: Starter turns every time. Fuel pressure is normal while running but I haven’t checked fuel pressure yet with the fuel pump relay removed and jumpered with the car not running.

Anyways, last weekend it wouldn't start again so I pulled the fuse/relay panel. After removing and cleaning/reseating the fuel pump relay, it started immediately and for the next 4 days I didn't have the issue again. However, problem reappeared this morning and it took 2 tries to get it to start.

I had assumed the relay was just making a poor connection in the colder weather and that was the problem, but apparently that's not the case. Questions:

- Do relays like this sometimes behave intermittently when they are starting to die? Or do they just die all at once?

- Is it safe to assume that camshaft position and crankshaft position sensors will throw codes when they malfunction?

- Have any of you ever experienced a bad pressure regulator on the filter causing intermittent issues like this when the vehicle is cold?

Thanks in advance for the help!!!