Track these three massive movers in the FTSE All-Share index

In this period of volatility, share prices are prone to especially sharp movements, something just demonstrated by this trio.

Confidence-boosting updates re-ignited buying interest in Halfords Group (LSE:HFD) and Avon Protection (LSE:AVON) today as the former FTSE 250-listed stocks set about recouping 2022’s heavy losses.

Their double-digit percentage share price gains were for sticking by previous guidance, highlighting just how much pessimism is currently baked into many valuations.

Avon, whose head protection and respiratory products are used by militaries and first responders, got the biggest boost after revealing that trading had improved in line with May’s last update. The full-year outcome should be “at least” in line with market expectations.

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Shares this afternoon traded at 1,000p for the first time since early August, but that’s a far cry from over 4,000p in November 2020 when the company was known as Avon Rubber and a hugely popular stock for retail investors.

A product testing failure that would ultimately lead to the winding down of Avon’s body armour business triggered the selling pressure in 2021 and throughout much of this year, despite support for defence-focused stocks following the Ukraine war.

Any fears that the body armour issues might have dented Avon’s relationship with the US Department of Defense continue to be allayed after a new contract worth $15.1 million today.

Analysts at Jefferies, who have a price target of 1,120p, said: “There continues to be plenty of work to do in terms of rebuilding the market's confidence in the group's outlook and the equity story, and today's update is a good start.”

Today’s share price acceleration for Halfords came after it stuck to guidance for profits of between £65 million and £75 million, having lowered City expectations in mid-June.

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Over 70% of sales are from motoring products and services, which Halfords pointed out today tend to be more needs-based rather than discretionary and are helping it to withstand the ongoing economic uncertainty.

Shares rallied 23.2p to their best level since mid-August at 156.7p but Peel Hunt thinks the shares should be back at June 2021 levels of 350p.

The broker called today’s update “highly positive” after an eye-catching performance by the Autocentres division, with the 19.4% like-for-like sales growth in the 20 weeks to 19 August pointing to considerable market share gains. In cycling, trading conditions were particularly tough after a 12.7% fall in underlying sales.

Peel Hunt said the current low forward valuation multiple of around five times earnings suggests that the market expects something to go really wrong: “We just don’t see it and with management delivering, and the balance sheet strong, there is a lot to like.”

Counterparts at Liberum are also supportive, but with earnings momentum on a negative trajectory they have kept their recommendation at “hold” until greater forecast confidence returns.

They added: “We like the service-led strategy, the growing mix of defensive and higher margin revenues and strong balance sheet, which will support further M&A in garages and an attractive dividend yield.”

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The third FTSE All-Share stock seeing double-digit percentage gains today was cyber security firm NCC Group (LSE:NCC), a move which reflected a combination of takeover speculation in the sector and a positive reception to results that yesterday showed profits doubled to £31 million.

Jefferies said the annual figures, which included underlying revenues growth of 10.3%, showed the company capitalising on the sizeable opportunity in cyber security and effectively managing sector-wide skills shortages.

The bank has a price target of 260p, which compares with 218.5p seen this afternoon after a rise of 20.5p.

Interest was also boosted by M&A activity after digital identity specialist GB Group (LSE:GBG) received an approach from Chicago-based private equity firm GTCR, days after Darktrace (LSE:DARK) revealed early discussions with Thoma Bravo.

GB’s AIM-listed shares jumped 118p to 640p, but Liberum said the fact that there have been five recent trade buyers of fraud and ID verification assets showed there could be other approaches.