I don't know if that source is reputable on its own, but two of the other quotes in the article are from Formu1a.uno. Assuming this article is a rewrite of other Formu1a.uno articles, it might be the writer mistranslated what they said about the two cars doing different tests. This was also mistranslated on Twitter, but a Formu1a.uno writer disputed it:
https://x.com/_Paolo_27/status/18086104 ... XRq2w&s=19
"Just to clarify, @GiulyDuchessa talked not about a comparison about cars (floor or whatever), the SF-24 will be fitted with all the upgrade and no other updates are expected. The comparison we talked is about the preparation of Qualyfing. Leclerc and Sainz will try diffrent outlaps, diffrent approach on how to do the Qualy lap to try to improve in that area. About bouncing just work on setup (aero and mechanical side, as correctly reported)"
This was two days ago. Of course, it's also possible something changed since then.