From Vodafone website:
$50 Prepaid Cap Starter Pack - now half price.
By signing up before 12 May 2015 you can enjoy all the benefits of the Vodafone $50 Prepaid Cap Starter Pack for only $25.
The Vodafone $50 Prepaid Cap Starter Pack comes with 3GB data and unlimited standard national calls and texts.
On top of this half price deal, you can take advantage of an additional offer that’s available until 2 August 2015. When you’re in Australia, you’ll have access to unlimited data on the weekends and infinite international calls to 10 selected countries. The Vodafone Fair Use policy applies.
Terms & conditions
Included Data
Data for use in Australia only. Once data inclusion is used, you will need to purchase a data pack or recharge to continue using data.
Half price $50 Cap Starter Pack
Offer available to customers who purchase a Vodafone Prepaid $50 Cap Starter Pack via shop.vodafone.com.au or in selected mass retail outlets by May 12 (inclusive) unless extended. $25 discount will be applied at checkout. Offer not available for commercial or resale purposes. Maximum 1 per customer. Standard Prepaid Starter Pack terms apply - please see packaging for more info. Not transferable and not redeemable for cash.
Unlimited Weekends
Personal use only. Offer available from 12am 7.2.15 to 11.59pm 02.08.15 (Offer Period). Free data and international calls is for usage between 12am Saturday and 11.59pm Sunday during the Offer Period. Available to either (a) existing customers with a valid $30, $40 or $50 Prepaid Cap recharge on 7.2.15 or (b) new and existing customers who activate a $30, $40 or $50 Prepaid Starter Pack or recharge on a $30, $40, or $50 Prepaid Cap during Offer Period. Free international calls apply to standard international voice calls to landlines and mobile numbers in China (excludes Hong Kong), India, USA, UK, and NZ. Offer only for use with a prepaid handset. Fair Use Policy applies, see http://www.vodafone.com.au/aboutvodafone/legal/fairusepolicy. Offer eligibility ceases if used for illegal purposes.
Is the half price only for the first month?