|(a) Penalty and interest will not apply to additional
value that results from retroactive price increases or retroactive
adjustments to value, provided that the additional tax is remitted
on or before the 20th day of the second month that follows the month
in which such price or value was determined. The taxpayer must notify
the comptroller of any tax that is not subject to penalty and interest.
(b) The gas purchaser is responsible for any tax, penalty,
and interest that accrues on gas that the purchaser takes whenever
the proceeds are not disbursed to the interest owners, unless the
producer is solely liable for the tax.