Correct.
Zero prospect of an election before 2028, Zero. Burnham is not stupid enough to risk being a 3 month Prime Minister, there's not going to be one this year. Even if he "won" a autumn 26 election his majority would be nowhere near what it is now so just stupid on every single level. He's not going to do that.
If everything goes great in the next two years (and/or Farage really fucks up, and/or we win the Euros ) he might risk summer '28 but the most likely is go all the way to Spring/Summer 2029.