"It was trading at a significant premium to the average of analysts valuation of around $6.50 on optimism it will continue to gain share in the Chinese infant formula market and margin expansion."
Windust said at above $8 the stock was pricing in a lot of share gains.
The market is now looking to A2 Milk's annual general meeting on November 21 to get an update on where it is headed.
"Without an upgrade the stock is vulnerable given the size of the share price rise."
A2 Milk shares recovered some lost ground yesterday and closed up 48c at $8.42.
Synlait Milk, the main supplier of A2 Milk, was also dragged down by A2's share price on Wednesday and recovered yesterday to close up 30c at $8.
BATTERY POWER
Australia's lithium producers are enjoying a meteoric run as the world's car makers increasingly look to battery powered vehicles, and as governments look to put the squeeze on gas guzzlers.
Western Australia's Pilbara - the world's biggest iron ore mining district - has seen fledgling lithium producer Pilbara Minerals sprout up from nowhere to ride the crest of the lithium boom.
The company's shares traded at A1c a piece in October 2013. In August - several capital raisings later - the stock was trading at A35c and closed yesterday at A84.5c.
The other producers - Galaxy Resources, Kidman Resources and Mineral Resources - have not done too badly either.
Now the big boys are getting involved, and ore giant Fortescue is looking for lithium in the Pilbara, not far from Pilbara Mineral's site at Pilgangoora.
About 2 per cent of the world's lithium demand comes from battery powered electric vehicles, but that is expected to soar to 60 per cent by 2020, according to Pilbara Minerals.
The company's latest surge has been put down to its deal with Chinese car maker, Great Wall, with which it has secured the first direct investment by a car manufacturer into an Australian supplier of raw lithium materials.
The equity investment deal, worth A$28 million ($31.2m), will see Pilbara supply the car maker with up to 150,000 tonnes of spodumene concentrate - a lithium source material - a year for use in its electric and hybrid vehicles.
The proceeds of the deal, which includes US$50m of debt financing, will fund the expansion of Pilbara's wholly-owned Pilgangoora Lithium-Tantalum project in Western Australia, the company said. Great Wall will indirectly own 3.47 per cent of Pilbara shares as part of the transaction.
"The landmark agreements represent a major endorsement of Pilbara Minerals as an emerging world-class, low-cost supplier of lithium raw materials," the company said.
DOWN LOW
Sky TV shares fell to another low this week continuing the company's ongoing share price slide.
The fall has prompted one analyst to upgrade its recommendation on the stock to accumulate after the price slide took it under $2.55.
In a note Morningstar's Brian Han said Sky TV enjoyed a high margin and had a highly cash-generative business model. "Its strong financial position and a stranglehold on key content have erected a competitive barrier that others have so far found difficult to breach."
But his upbeat view on the stock also came with a warning that emerging distribution channels were likely to allow content providers to by-pass Sky TV and go straight to consumers.
While at the same time consumers were likely to become less willing to pay for traditional channel bundles.
"All these long-term dynamics are likely to put pressure on the company's operating metrics and cost structure."
Sky TV's shares have fallen 44.4 per cent in the last year and yesterday closed up 4c at $2.50.
