Rockin Blueberry

I planted a Blueberry in a 5 litre pot full of ericaceous comost in March 2014. It grew well through the summer so in November 2014 I upgraded it to a 10 litre pot. It continued to thrive this spring and has produced a good crop of berries. Last week during the strong wind and rain  it started flopping about in the pot. I added a bit more ericaceous compost and firmed it in but did not solve the problem.  Solutions I am considering are:

1- Tie the plant a cane to be put in the pot,

2- Cut the plant back hard to stimulate root growth

3- lighter version of 2, simply remove all fruit hoping to stabilise it.

4- Repot and incorporate soil with the compost.

Anybody had this problem and know what the best solution is?