Visa appointment date may be up to six months before the visa start date
Income rules are more broadly a "test of resources" as savings are taken into account when necessary.
The income requirement rules are the same for both the VLS-T and VLST-TS visas.
Since autumn 2022 the broad test of resources is around £2000 per month (GBP not Euro) for a couple and remains at SMIC Net for a single person. SMIC Net, the net French minimum wage. In May 2024 it is about Euro 1400 per month The monthly rate does change, it has increased by 60 Euros over the last 18 months. You can find the value here: https://www.service-public.fr/particuliers/vosdroits/F2300?lang=en then scroll to "What is the amount of SMIC"
This income must be 'stable et régulière' .
If unable to meet the minimum income requirement, you may use capital or a mix of capital and income to satisfy the “test of resources” needed for the full period of the visa.
This is a broad rule that carries the caveat that the "project" of the applicants will be considered on its merits. If you own your own property with no mortgage this will be taken into account.
This summary information is based on a detailed article by France-Insider issued in September 2022 and re-verified on 30/10/2022. It is published with their permission. The article is behind a paywall (€20 per year at present)
Ensure that you document your income carefully
An applicant was recently refused a visa on the basis of income. It appears that they just provided bank statements without any, or with minimal, guidance as to how they were interpreted.
See the Docs for Appointment page for more detail here