Technical Unclip heater core inlet hose

[Oz500]

Help please?
I need advice on how to unclip the heater core inlet hose fitting from the heater core.
I have ordered a new (genuine) heater core inlet hose (part 4 in first image; part 1 in second image), and I cannot work out how to unclip the old one.

The attachment seems to have two side metal tabs (slightly different to each other); pushing them in, back (towards firewall/bulkhead) or forwards makes no difference.

 

[Oz500]

As you probably realise, you need to press the 2 metal tabs so that the metal band they connect to comes out of the groove in the plastic stub, allowing the pipe to slide off the stub.
Which sounds easy, but sometimes isn't.
Hopefully pictures will help with the theory. They can put up a fight, but eventually let go.
I have had to resort to using a jubilee (worm drive) clip once in the past, but usually finger pressure works.
Sometimes a third hand is helpful.

You are a legend!
thankyou

 

[Oz500]

I have had to resort to using a jubilee (worm drive) clip once in the past, but usually finger pressure works.

The jubilee clamp suggestion is a winner!
The pic below shows what the pipe looks like with that connection removed - and even using the hose clamp/jubilee clamp to squeeze the two metal tabs, it was still a challenge to make it let go.