TBO Question on 912ULS

Assuming you are talking about a 912ULS, you appear to be correct.
The SB refers to SN. 6775790 and above as 2000/15 TBO.  You are Below.
So, it looks like without the extra servicing, you are looking at a 1500/12 TBO engine.

This makes little difference as at the current rate, it will take another 15 years to get to 1200 hours.
But, you are already beyond even the 15-year limit.  Game Over!

If it is an LSA, you will need to follow Tecnams rules.
If it is an Experimental, you can fly "On Condition" 'til the end of time.

FYI: 5647379 was indeed produced 30-Oct-2006

Engine Type 912 ULS2

Description

without fuel lines

UL2 I=2,43 with clutch

without vacuum pump

with green valve covers

without mech. tachom. pick up

without external generator

without air guide baffle

with std. temperatur sensors

with nipple conn. for oil pump

with expansion tank

without air box

without engine truss

starter large

The only way for you to get the 2000hr TBO is to have the crankcase changed to the new style ("Heavy Case). The new style crankcase came out in 2007, so you are shy of that, unfortunately.

Each country has its own regulatory authority which sets the rules for that region. Some are the same from region to region and some are different. The FAA sets the rules and regs for the US and an aircraft company can not give away the farm or require rules or regs above what's in the US FAR's. Below is a quote from the FAA legal and the attachments are from the FAA legal department commenting on TBO regulations.

Bottom line each aircraft MFG must stay within its regulatory rules and regs.

FAA legal quote:

Each person performing maintenance, alteration, or preventive maintenance on an aircraft, engine, propeller, or appliance shall use the methods, techniques, and practices prescribed in the current manufacturer's maintenance manual or Instructions for Continued Airworthiness prepared by its manufacturer, or other methods, techniques, and practices acceptable to the Administrator. (FAA),

except as noted in § 43.16. I

Part 43 does not mandate that a person specifically perform maintenance, alteration, or preventive maintenance solely in accordance with those instructions specified in a manufacturer's maintenance manual. It also permits a person to perform such work in accordance with other methods, techniques, and practices acceptable to the administrator. 

Section 43.16 refers to Airworthiness Limitations. A person performing an inspection or other maintenance specified in the Airworthiness Limitations section ofa manufacturer's maintenance manual must perform that work in accordance with that section or as otherwise specifically approved by the Administrator. Maintenance manuals for S-LSA do not have an Airworthiness Limitations section to which the provisions of this section would apply.

Further to Rogers advice;

In Australia TBO for Rotax (& presumably other engines) is really only of concern to aircraft that are to be used commercially (hire & training).

Only aircraft that have been built by the factory, can be used for commercial purposes.

An aircraft used for commercial purposes must have the engine replaced/recertified at TBO, if the aircraft is to continue as a commercial venture.

Our rules allow for a non commercial aircraft/engine to be used "on condition" indefinitely (this includes factory built aircraft).

Quite a few purchasers of, preloved, aircraft get very excited by TBO and pay substantially more for an aircraft whose engine is within TBO but then go on to do only 50 hrs per year and don't hire out their aircraft - go figure.