TDS payment due date for March month is 30th April. You are also correct but this section was amended in last year budget so now only a single payment date is announced for payment of March month TDS is 30th April.
26 April 2012
•Section 40A(3)(a) of the Income-tax Act, 1961 provides that any expenditure incurred in respect of which payment is made in a sum exceeding Rs.20,000/- otherwise than by an account payee cheque drawn on a bank or by an account payee bank draft, shall not be allowed as a deduction.However if payment is being made for plying, hiring or leasing goods carriages then Limit for these section is Rs 35000/-,instead Of 20000/-
So, It is for Business Expenditure. You can pay more than 20,000/- for any Capital Expenditure there is no restriction.