Etihad Airways is the latest airline to tweak its frequent flyer scheme, and as is so often the case the changes to Etihad Guest hold upsides and downsides for different travellers.

Here's a rundown of the changes, which come into effect from July 8, 2015.

Fuel surcharges are out, carrier charges are in

"The fuel surcharges that have traditionally been levied on some GuestSeats into Abu Dhabi will be removed", Etihad says – but don't cheer too soon.

There'll now be a new 'carrier charge' added to all GuestSeat bookings of US$50 per sector in economy class, US$100 per sector in business class and US$150 in first class.

Earning Etihad Guest Miles

Etihad airfares fall into one of a bewildering 13 ticket classes, from the cheapest economy seats to that plush 'penthouse in the sky' known as The Residence.

Five of those fare classes – including first class 'R', business class 'D' and three economy categories – will in future offer more miles than they do today, whilst two fare classes – business class 'Z' and economy 'E' – will offer fewer miles. Click here to see the full list on Etihad's website.

Using Etihad Guest Miles for 'GuestSeats'

A number of seats on each Etihad flight are set aside for 'purchase' by redeeming Guest Miles or a 'Miles plus Cash' mix (up to 25% of the fare can be paid for).

As of July 8 there'll be a shuffle in the amount of Guest Miles needed for GuestSeats, with 'sectors' of 6,000 miles emerging as the break point.

To put that into perspective: it's just under 7,500 miles for a flight between Sydney and Etihad's hub at Abu Dhabi, and just over 3,400 miles between Abu Dhabi and London.

You'll need more Etihad Guest miles to buy your business class seat under 6,000 miles, although for sectors beyond 6,000 miles (which covers all flights between Australia and Abu Dhabi) you'll need 25% fewer Etihad Guest miles than today to book an economy seat.

The amount of Etihad Guest Miles needed to snare a seat in First Class will increase across all flights.

More GuestSeats per flight

"In line with the growing demand from members, the minimum number of GuestSeats available in Business Class on some of our highest demand routes will increase by 20%" the airline promises, citing an extra 1,000 business class seats each month "on popular routes."

There'll also "be a minimum of five GuestSeats available in Economy Class on every flight."

Using Etihad Guest Miles for OpenSeats

From July 8 you'll be able to trade your Etihad Guest Miles for the airline's lowest available "breaking deals' airfares in business class and economy.

There's also be a member-only discount "of up to 30% on the commercial fare" for business and first class on popular routes – such as Abu Dhabi to Sydney, London, Istanbul and Bangkok – but with the caveat of contributing "a fixed minimum number of Etihad Guest Miles towards the fare".

Using Etihad Guest Miles for Upgrades

This one's going to sting a little. On the whole, the number of Etihad Guest Miles needed for an upgrade will increase, while miles will no longer get you an upgrade from 'breaking deals' economy or business class fares.

Also read: The unofficial Etihad Guest guide for Aussie frequent flyers 

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