Sapsucker... Red-naped or Yellow-bellied

A sapsucker has been mewing on our farm for months. I have not been able to get good photos yet. Listers who have been here insist it is a Yellow-bellied. But Yellow-bellied Sapsuckers do not get adult plumage, according to Sibley, until March. This bird now has a red forehead and red throat. I will post the first blurry photos from January 28, 2019. Clearly a juvenile. It appeared to have, in my brief previous glimpses, a yellowish belly.

 But in this 1//28/19 photo, it appears to have a bit of red at the throat and possibly on top of the head. Possibly. Lousy photo.

 
I assumed I was seeing the same bird on Feb.4 when I took these blurry photos. If the same bird, it had changed a lot in 6 days. gone is the brownish upper chest. Now it clearly has a red forehead and at least partial red throat.

That same day, two listers came out and caught brief glimpses, declaring it a Yellow-bellied because it was still in juvenile plumage this time of year. The bird then disappeared until Feb. 10. Another lister came out, caught a brief glance, and agreed with the first two listers.

I don't know if the bird of Jan. 28 is the same as the bird of Feb. 4 and 10. I don't know if the bird of Feb. 4 could be considered in "juvenile plumage".

Any help by anyone knowing about plumage changes in sapsuckers would be most appreciated.

I am not inviting birders out to view it for a time as it seems shy and easily scared off. I would like it to stick around.

Thanks to Dave Irons for his reply:

On 2/11/2019 4:05 PM, David Irons wrote:
Looks like a fair amount of juvenile plumage retained, which makes this a Yellow-bellied Sapsucker rather than one of the other two species. Everything that I can see from the better photos suggests Yellow-bellied. I see no red on the nape.
Dave Irons
Beaverton, OR

and...

A first-winter Yellow-bellied Sapsucker could well be molting right now. They usually most late winter/early spring and will look like adults by March or so.

Dave 

On 2/15/19, the bird returned and mewed all morning from trees next to our house. I took these photos: