Thank you soooo much, this is exactly what I wanted to do. I’m placing a screenshot and steps in case anybody else needs it for future reference.
Step 1: Go to “Edit Observations” under the profile image on the top right-hand side of the webpage.
Step 2: Select the “Batch Edit” option next to Add Observations and select the observations you want to edit based on your parameters.
Step 3: Click on “Edit Selected” which will take you to a new web page showing a list of your selected observations to edit
Step 4: Click on the “Batch Operations” drop-down in the yellow box and select the radius you want to apply to the selected observations, you will then need to scroll down to the bottom of the page and press the “Save All” option.