Slow Custom Domain response time in Oceania compared to webflow.io domain

We are encountering an issue with Webflow where it is slow to serve HTML from custom domain in Oceania compared to a default Webflow.io domain

Observe the following examples. 2 Sites. Both on business plan

GlamCorner Default Webflow: https://www-glamcorner-com-au.webflow.io
GlamCorner Custom Domain: https://production-webflow.glamcorner.com.au

Ikaros Default Webflow: https://ikaros.webflow.io
Ikaros Custom Domain: https://www.ikaros.io

When tested by GTmetrix from Vancouver, Canada the TTFB between these sites are within small margin of each other:

GlamCorner Default Webflow TTFB: 85ms
GlamCorner Custom Domain TTFB: 108ms

Ikaros Default Webflow TTFB: 57ms
Ikaros Custom Domain TTFB: 68ms

However when tested from Sydney, Australia the TTFB between sites becomes very large:

GlamCorner Default Webflow TTFB: 18ms
GlamCorner Custom Domain TTFB: 447ms

Ikaros Default Webflow TTFB: 30ms
Ikaros Custom Domain TTFB: 0.6s

Reaching out to community to see if anyone experienced similar issue or has a Webflow site on a custom domain that I could run through GTmextrix to gather more data

Vancouver and Fiji are both on pacific links and Australia is on a spur? But there’s a lot of great design in Australia and on .au respect.

Got a reply from the support team.

webflow.io goes though CND, which is wordwide.
Custom Domain goes to AWS and then to CND. Closest one is in Japan