Overwrite With New Edited Image - Keep Same Name

One of my clients asked me to review one of his websites hosted on Squarespace.  I used Google Lighthouse to see how it did on Performance, SEO, etc.  Performance was 24% with the reason being large image sizes.  The person/s doing the site were photographers but the high quality was dragging down the performance.  I tried a few compression tools and found significant savings.  That would really boost the page load speed while keeping an acceptable visual quality.  I've never worked with Squarespace before so am hoping this forum might help me hit the ground running.  What I want to do is be able to upload the original that's been reduced and keep the original name so it doesn't have to be re-linked (hundreds of pictures).  Any help appreciated.  Thanks.

When images are uploaded to Squarespace they are stored on a global CDN and so are given unique Squarespace URLs, not ones that relate to the domain of the website.  These cannot be replicated so if an image is replaced, the url will change. If this isn’t what you mean, please provide a few more details including a working link to a page on the site.