If you take a look at MicroK8s’ channel information with snap info microk8s you will see all available Kubernetes releases:

channels:

stable: v1.14.1 2019-04-18 (522) 214MB classic

candidate: v1.14.1 2019-04-15 (522) 214MB classic

beta: v1.14.1 2019-04-15 (522) 214MB classic

edge: v1.14.1 2019-05-10 (587) 217MB classic

1.15/stable: –

1.15/candidate: –

1.15/beta: –

1.15/edge: v1.15.0-alpha.3 2019-05-08 (578) 215MB classic

1.14/stable: v1.14.1 2019-04-18 (521) 214MB classic

1.14/candidate: v1.14.1 2019-04-15 (521) 214MB classic

1.14/beta: v1.14.1 2019-04-15 (521) 214MB classic

1.14/edge: v1.14.1 2019-05-11 (590) 217MB classic

1.13/stable: v1.13.5 2019-04-22 (526) 237MB classic

1.13/candidate: v1.13.6 2019-05-09 (581) 237MB classic

1.13/beta: v1.13.6 2019-05-09 (581) 237MB classic

1.13/edge: v1.13.6 2019-05-08 (581) 237MB classic

1.12/stable: v1.12.8 2019-05-02 (547) 259MB classic

1.12/candidate: v1.12.8 2019-05-01 (547) 259MB classic

1.12/beta: v1.12.8 2019-05-01 (547) 259MB classic

1.12/edge: v1.12.8 2019-04-24 (547) 259MB classic

1.11/stable: v1.11.10 2019-05-10 (557) 258MB classic

1.11/candidate: v1.11.10 2019-05-02 (557) 258MB classic

1.11/beta: v1.11.10 2019-05-02 (557) 258MB classic

1.11/edge: v1.11.10 2019-05-01 (557) 258MB classic

1.10/stable: v1.10.13 2019-04-22 (546) 222MB classic

1.10/candidate: v1.10.13 2019-04-22 (546) 222MB classic

1.10/beta: v1.10.13 2019-04-22 (546) 222MB classic

1.10/edge: v1.10.13 2019-04-22 (546) 222MB classic

If you want to follow the v1.14 Kubernetes releases you would:

sudo snap install microk8s --classic --channel=1.14/stable

Whereas if you always want to be on the latest stable release you would:

sudo snap install microk8s --classic

What is new in the channels list above is the pre-stable releases found under the 1.15 track (at the time of this writing the latest stable release is v1.14).