Soon after moonrise yesterday was around 4:30 PM. The background wasn't dark yet at that time. The photo must have been taken later at the evening. I've taken a lot of pictures of the moon and most of them show the moon to be yellow:
By "soon after moonrise" I meant about an hour after moonrise. When I was cycling home around 6:00 PM, the moon already was rather high and whitish.
As I said above, the contrail hypothesis is verifiable provided the exact time of the photo is known. The moonrise in Bristol yesterday (January 22, 2016) was at 15:31 at 61° (ENE). The Moon elevation and azimuth at any time are also known/can be readily calculated. For example, at 18:00 they were 20° and 88° (E), respectively:
http://www.timeanddate.com/moon/uk/bristol
All one needs afterwards is to check the FR24 (or any other flighttracker) playback for planes in the Moon's direction, which were at a right distance from Bristol to pass across the Moon at a given elevation.
PS For the time of 16:50 this private jet would be a very good candidate:
The white line's heading corresponds to the Moon azimuth at the time, 75°, and its length is about 79 km (from the scale bar at the bottom right corner). This is close to the calculated length of 75 km from the plane altitude (43,000 ft = 13.1 km) and the Moon elevation, 10°.
The aircraft of this type usually have thinner contrails compared to passenger planes.