It said in the press release that Lotus Group was a title sponsorship, the chassis would remain Renault. Regardless the current Renault team would appear as Lotus Renault compared to the current Lotus team who would appear as Chassis - Engine: Lotus - Renault.
But given that sponsors aren't listed in the constructor table when highlighted on the F1 broadcast or even on the F1 website, Lotus groups team will appear as Renault as both chassis and engine would be Renault.
In the post race press conference James Allen calls the teams with their sponsors too, and on the FIA website they have the entire entrant with sponsor, eg Vodafone McLaren Mercedes, Scuderia Ferrari Marlboro so there they would be Lotus Renault.
