No, the new IQOS 3 DUO Pocket Charger is only compatible with IQOS 3.
If you insert the IQOS 2.4+ Holder into the IQOS 3 DUO Pocket Charger, the Holder will not fit because of different size.
If you accidentally insert the IQOS 3 DUO Holder in the IQOS 2.4+ Pocket Charger, the Pocket Charger lights will start blinking, however, the Holder won’t charge.