If you know the date you want, you can easily find the posts for that date and earlier. For example if you want 11th January 2020, type this in the internet address bar:
http://pembsbirds.blogspot.com/search?updated-max=2020-01-12T00:00:00Z
(N.B. Alternatively you can search by month going right back to January 2008 using the Archive facility just below Links on the right hand side of the blog. To find posts on a particular species or place type in the name in the search box top left of the blog and hit enter. This is rather hit and miss with results in no particular order. Rich Crossen)