Abatement for Rent a Cab Service

If a service provider providing Rent a Cab service for which abatement is available at 60% of gross value of taxable value vide notification 1/2006.

Can he do the multiple transactions i.e. billing Service Tax at 4.12% where his customers are asking to charge service tax at abated rate.

And can he charge Service Tax at full rate i.e. @ 10.30% where his customers are not asking to bill at abated rate of service tax. Pls advice.