I think Sportsbet.io and Newcastle will continue the partnership with each other.
According to the announcement made by Newcastle United in August 2023 when the partnership was started, they have a multi-year partnership.
From Newcastle United official website:
Newcastle United has announced a multi-year partnership with Sportsbet.io, a leading online sports technology and betting platform
It looks a long partnership between Sportsbet.io and Newcastle United but this can potentially be affected by policy changes in England. Their government have been considering possible strategic national changes entirely in sports and gambling marketing and advertisements, so they might let it be like now or tighten it more in upcoming years.
I believe both Sportsbet.io and Newcastle United are all aware of this possible changes and perhaps in their partnership contract, there are terms for partnership adjustment according to national regulatory changes - that are not publicly disclosed.