First, the b..........s in Cantberry wont actually know unless specifically advised, or they happen to carry out an audit, but as already noted, the consequences of over-running could be disasterous.
Remember, it is the responsibility of the registered operator to ensure that all required maintenance is carried out as due, and failure to do so invalidates airworthiness, insurance, and incures the personal liability risk as well as legal risk.
If you are the registered operator, then the following may be of help in the future.
You say "bugsmasher", so I tend to think that the aircraft will be in private or airwork categories, if so talk to your friendly local LAME, or CASA rep about changing the logbook statement to remove the 100 hourly requirement for issue of MR - note that this does not remove the requirement to have 100 hrly maintenance carried out as per maint manual, but does remove the requirement to have new MR issued every time - there will still be a max 12 month duration of the MR.
If the logbook statement already shows "unlimited hours" (or words to that effect) then your current MR has been issued in errot if it shows a 100 hr duration. This is of no help currently, as it WILL expire at the hours / date specified. However, if issued in error, your maint org may elect to try and assist you in some way if approached tactfully.
Your other consideration is to be aware of how the hours are recorded - the requirement is to record FLIGHT time, not engine running time, or time that the master switch is turned on. As long as you record flight time accurately and your method of recording is not in conflict with the operators standard requirements, then you might find you can stop loosing hours that normally go to taxy and holding time. With regard to that, I know of flight training schools that have two hourmeters fitted, one to record flight time (maint) and one to record engine running time (charge the customer).
Happy flying,
Tite