How to set the default map location on all map blocks

Site URL: http://www.leigharttrail.com/artists-2019/venue-1-ian-smith-painter

Hello, is there a way to set by the default location of the map block, that currently is set to New York, USA. I ask this as my site is for an Art Trail, that has had to be postponed due to Coronavirus. Therefore my client wants the site live but with now venue locations at this time. So I like to set a default location of all the maps featured on the blog post to just show the town that the art trail is in, eg. Leigh-on-Sea, UK. This is the address location that centres the default map correctly 125-127 Broadway, Leigh-on-Sea, Southend-on-Sea, Leigh-on-Sea SS9 1PG 

Is there a way to do this once for all maps placed in my blog page design? Thank you