For the most part, yes. Capital allowances claims, particularly for property expenditure, are often under-stated.
No. For claims on plant and machinery fixtures, there is usually no impact.
There isn’t one ...
The tax relief from a capital allowances claim can be carried back (loss carry back rules apply) or carried forward to reduce future tax liabilities.
It is a general misconception that there is a time limit on claiming capital allowances. Providing you still own the assets to be claimed, there are no time restrictions to make a claim on historic expenditure.