Thai Airways is on a roll with upgrades to many Australian routes, although it's a bit of a mixed bag for Sydney.

Here's a rundown for business travellers headed to Bangkok and beyond.

Sydney is already seeing Thai's revamped Boeing 747s with the swish new Royal First Class Suites designed by London-based design firm Priestmangoode.

The look was inspired by Thailand's spa retreats, with shades of gold and purple reflecting the Thai Airways brand colours complemented by muted grey tones and accents of wood.

This includes wooden angled privacy louvres enable passengers to see out but prevent others looking in to each suite.

The not so good news? You'll see these jazzed-up jumbos less often, with Thai trimming its Sydney-Bangkok service back to 10 flights as week from the current twelve as of April 29 through to October 25.

Brisbane has already enjoyed a bump-up to Thai's Boeing 777-300ER, although Thai Airways tells Australian Business Traveller that the plane will be pulled off the route from June 15.

It'll be back from October 1 to 25, Thai promises, although the schedule past October 26 is still to be decided.

Melbourne is getting Thai's new Boeing 777-300ER from March 30 on some of the TG465/466 flights, but you'll need luck on your side come departure day. A Thai Airways spokeswomen told Australian Business Traveller that it’s “not clear which days which aircraft will operate – it could be any day”.

Of course, Perth will move to centre stage on July 1 with the debut of Thai's first Boeing 787 Dreamliner service.

The Dreamliners will be fitted with 24 seats in Thai's Royal Silk business class and 240 in economy, and feature the new 'Thai Contemporary Concept' design now being rolled out on the airline's Boeing 777-300ERs.

Although this will be Perth's first Dreamliner service, it will be followed barely three months later by the mid-October launch of Air New Zealand's Boeing 787-9 on the Auckland-Perth route.

Read: Air New Zealand gears up for Boeing 787-9 Dreamliner’s debut

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