Its not unusual for whole of life policies to be reviewed.
Its difficult to calculate a premium over a 'lifetime' e.g. if a 70/80/90 year period was used for the initial calculation, the premiums would be huge. Therefore, the premium for a whole of life policy is usually calculated for a set no. of years e.g. 25.
At the beginning the premium may be higher than the actual cost of the life assurance. The difference (premium - life cover costs) accumulate so in later years when the cost of the life cover increases, the premiums don't necessarily increase straight away as it eats into the earlier overpayments.
The policy is reviewed at set intervals and if there are enough funds available, the premium won't increase. Unfortunately when the funds run out and the life cover costs increase (due to age and increased risk) the premiums increase.
It is difficult for anyone to recommend a policy as it depends on your personal circumstances. Shop around but don't cancel your current life cover plan until another policy is in place.