Very nice indeed James, I had a Yellow wagtail last week, so there were certainly birds arriving earlier than anticipated. I suspect you are onto something with regards to disturbance - certainly appears as though birds are more confiding when there are less people around, and as a result more noticeable.

Sorry, no photos.  With current lockdown I feel a little guilty stopping on my “daily exercise” to take photos.  Agree they felt a little early, but got good views of 4 Tree Pipits and the Whinchat so fairly confident with the ID.  Not surpisingly at the moment the hills are empty of people - not sure whether that is making any difference in the visibility of early arrivals.  A quick google shows ids of Tree Pipit at Holme Bird Observatory (Norfolk) on 27th March so not quite the earliest.  Also seen in Kent on 1st Apr so definitely a few are around at the moment.

Interesting sightings, I think that your reports of multiple Tree pipits and a Whinchat are the first in the UK this year, they’ve not even appeared at Portland yet. The average arrival for those two species at Portland is 6th April and 16th April respectively, so very early indeed. Did you manage any photos?

Growing number of summer visitors/spring migrants on my daily walk on West Quantocks.  Lots of Blackcap and Tree Pipits.  Single Whinchat and Red Kite.  Meadow Pipits in very large numbers (more than normal it seems - not sure whether this is due to relatively mild winter)