WordPress Mobile Speed Optimisation

My WordPress site is currently scoring 30 on Google PageSpeed Insights for mobile.

I am looking for a specialist who can audit the site and bring the mobile PageSpeed score to a minimum of 75, ideally 80+, without rebuilding the site or changing the CMS. The site must remain on WordPress with WPBakery as the page builder, as I manage all content editing myself.

WHAT I NEED DONE
A full performance audit identifying what is causing the low score, followed by implementation of fixes. This typically includes image compression and next-gen format conversion, caching configuration, plugin audit and removal of unnecessary load, render-blocking JavaScript and CSS deferral, and Core Web Vitals optimisation (LCP, CLS, FID/INP).

WHAT I DO NOT WANT
No theme changes, no page builder changes, no structural rebuild, no migration away from WordPress. The site must look and function identically after the work is done.

WHAT I WANT TO SEE IN YOUR PROPOSAL
Your before/after PageSpeed scores from previous WordPress speed projects, specifically mobile scores. A clear statement of what score you are confident you can achieve on my site. Whether you offer a guarantee tied to hitting a minimum score. Your timeline from start to completion.

SITE DETAILS
Built on WordPress with WPBakery. Hosting provider can be confirmed on request. CDN is Cloudflare.