dropping out of a levels and doing them next year instead

i don't think im going to do that well in my a levels. it's looking like 3 As if that but I want A*s for my course and uni preferences. if i drop out this year and avoid the risk of doing badly and eliminating preferred options, will unis like LSE or cambridge care too much that i did them a year later if i also specify an actual reason as to why I had to? can it really affect my applciation next year? if i were to specify a reason, does anyone know what they take seriously? i do have somewhat of a reason but not sure how seriously theyll take it.

also if i were to get an offer frmo lse this year but dont want to risk doing badly in a levels and eliminate the chance of even being accepted through entry next year so drop out of a levels instead, will lse also take into consideration that i previously had an offer

im not applying for hugely competitive courses. still competitive because of the uni but not hugely oversubscribed like pure econ. im applying for econ and phil at lse and potentially land econ at cambridge if i reapply next year because i didnt apply this year