Mako Mermaids Movie in the works (Weilan and Sirena possibly returning)

Apparently, it looks like a movie will be the next follow-up of Mako Mermaids instead of another season. There is no official confirmation yet but a few hints can be found on director's twitter and instagram:

"Next is a movie"
https://twitter.com/ufojmsp/status/639947064026116096

"More #makomermaids tails to come..."
https://twitter.com/ufojmsp/status/737805780632535040

"Thanks Shanghai! Can't wait till #makomermaids movie brings Weilan home."
https://www.instagram.com/p/8ICKbNqa77/?taken-by=jmsp1

I hope we will get some official news soon...

Edit:
Amy Ruffle: "You may see Sirena again"
https://twitter.com/AmyRuffle1/status/736367291999215616